A few monolayers of organic semiconductors adjacent to the dielectric layer are of vital importance in organic field-effect transistors due to their dominant role in charge transport.In this report,the 2-nm-thick poly...A few monolayers of organic semiconductors adjacent to the dielectric layer are of vital importance in organic field-effect transistors due to their dominant role in charge transport.In this report,the 2-nm-thick polymer monolayers based on poly(3-hexylthiophene)with different molecular weights(M_(n))were fabricated using dip-coating technique.During the monolayer(solid state)formation from the solution,a disorder-to-order transition of polymer conformation is observed through UV-vis absorption measurement.Meanwhile,high Mn polymer monolayer generates higher crystalline fibrillar microstructure than the low Mn one due to the strongerπ–πintermolecular packing between polymers.More importantly,the solution aging procedure is utilized to further improve the morphology of polymer monolayers.It is obvious that after aging for 6 d,both fiber dimension and density as well as conjugation length are significantly increased under the same processing conditions in comparison to the fresh solution,and consequently the field-effect mobilities are remarkably enhanced by 2—4 times.Note that the maximum mobility of 0.027 cm2·V^(–1)·s^(–1)is among the highest reported values for poly(3-hexylthiophene)monolayer transistors.These results demonstrate a simple but powerful strategy for boosting the device performance of polymer monolayer transistors.展开更多
基金This work is supported by the National Key R&D Program of China(No.2019YFA0706100)the National Natural Science Foundation of China(Nos.62074163,61890944,61720106013)the Strategic Priority Research Program of Chinese Academy of Sciences(Nos.XDB30030000,XDB30030300).
文摘A few monolayers of organic semiconductors adjacent to the dielectric layer are of vital importance in organic field-effect transistors due to their dominant role in charge transport.In this report,the 2-nm-thick polymer monolayers based on poly(3-hexylthiophene)with different molecular weights(M_(n))were fabricated using dip-coating technique.During the monolayer(solid state)formation from the solution,a disorder-to-order transition of polymer conformation is observed through UV-vis absorption measurement.Meanwhile,high Mn polymer monolayer generates higher crystalline fibrillar microstructure than the low Mn one due to the strongerπ–πintermolecular packing between polymers.More importantly,the solution aging procedure is utilized to further improve the morphology of polymer monolayers.It is obvious that after aging for 6 d,both fiber dimension and density as well as conjugation length are significantly increased under the same processing conditions in comparison to the fresh solution,and consequently the field-effect mobilities are remarkably enhanced by 2—4 times.Note that the maximum mobility of 0.027 cm2·V^(–1)·s^(–1)is among the highest reported values for poly(3-hexylthiophene)monolayer transistors.These results demonstrate a simple but powerful strategy for boosting the device performance of polymer monolayer transistors.
